[Code of Federal Regulations]
[Title 21, Volume 2]
[Revised as of April 1, 2006]
From the U.S. Government Printing Office via GPO Access
TITLE 21--FOOD AND DRUGS
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN
PART 137_CEREAL FLOURS AND RELATED PRODUCTS--Table of Contents
Subpart B_Requirements for Specific Standardized Cereal Flours and
Sec. 137.180 Self-rising flour.
(a) Self-rising flour, self-rising white flour, self-rising wheat
flour, is an intimate mixture of flour, sodium bicarbonate, and one or
more of the acid-reacting substances monocalcium phosphate, sodium acid
pyrophosphate, and sodium aluminum phosphate. It is seasoned with salt.
When it is tested by the method prescribed in paragraph (c) of this
section not less than 0.5 percent of carbon dioxide is evolved. The
acid-reacting substance is added in sufficient quantity to neutralize
the sodium bicarbonate. The combined weight of such acid-reacting
substance and sodium bicarbonate is not more than 4.5 parts to each 100
parts of flour used. Subject to the conditions and restrictions
prescribed by Sec. 137.105(a), the bleaching ingredients specified in
such section may be added as optional ingredients. If the flour used in
making the self-rising flour is bleached, the optional bleaching
ingredient used therein (see Sec. 137.105(a)) is also an optional
ingredient of the self-rising flour.
(b) Label declaration. Each of the ingredients used in the food,
shall be declared on the label as required by the applicable sections of
parts 101 and 130 of this chapter.
(c) The method referred to in paragraph (a) of this section is the
method prescribed in ``Official Methods of Analysis of the Association
of Official Analytical Chemists'' (AOAC), 13th Ed.
(1980), section 8.002, ``Reagent (Displacement soln.),'' and section
8.003, ``Chittick apparatus,'' under the heading ``Total Carbon Dioxide
(1)--Official Final Action,'' which is incorporated by reference. Copies
may be obtained from the AOAC INTERNATIONAL, 481 North Frederick Ave.,
suite 500, Gaithersburg, MD 20877, or may be examined at the National
Archives and Records Administration (NARA). For information on the
availability of this material at NARA, call 202-741-6030, or go to:
regulations/ibr--locations.html.The following procedure is substituted
for the procedure specified in the AOAC, under section 8.004,
(1) Weigh 17 grams of the official sample into flask A, add 15-20
glass beads (4-6 mm. diameter), and connect this flask with the
apparatus (fig. 22). Open stopcock C and by means of the leveling bulb E
bring the displacement solution to the 25 cc. graduation above the zero
mark. (This 25 cc. is a partial allowance for the volume of acid to be
used in the decomposition.) Allow the apparatus to stand 1-2 minutes to
insure that the temperature and pressure within the apparatus are the
same as those of the room. Close the stopcock, lower the leveling bulb
somewhat to reduce the pressure within the apparatus, and slowly run
into the decomposition flask from burette F 45 cc. of sulfuric acid
(1+5). To prevent the liberated carbon dioxide from escaping through the
acid burette into the air, keep the displacement solution in the
leveling bulb at all times during the decomposition at a lower level
than that in the gas-measuring tube. Rotate and then vigorously agitate
the decomposition flask for three minutes to mix the contents
intimately. Allow to stand for 10 minutes to bring to equilibrium.
Equalize the pressure in the measuring tube by means of the leveling
bulb and read the volume of gas from the zero point on the tube. Deduct
20 cc. from this reading (this 20 cc. together with previous allowance
of 25 cc. compensates for the 45 cc. acid used in the decomposition).
Observe the temperature of the air surrounding the apparatus and also
the barometric pressure and multiply the number of mL of gas evolved by
the factor given in section 52.007, ``Correction factors for gasometric
determination of carbon dioxide,'' AOAC, 13th Ed. (1980), which is
incorporated by reference (the availability of this incorporation by
reference is given in paragraph (c) of this section), for the
temperature and pressure observed. Divide the corrected reading by 100
to obtain the apparent percent by weight of carbon dioxide in the
(2) Correct the apparent percent of carbon dioxide to compensate for
varying atmospheric conditions by immediately assaying a synthetic
sample by the same method in the same apparatus.
(3) Prepare the synthetic sample with 16.2 grams of flour, 0.30 gram
of monocalcium phosphate, 0.30 gram of salt, and a sufficient quantity
of sodium bicarbonate U.S.P. (dried over sulfuric acid) to yield the
amount of carbon dioxide recovered in assay of official sample.
Determine this quantity by multiplying weight of carbon dioxide
recovered in assay of official sample by 1.91.
(4) Divide the weight of carbon dioxide recovered from synthetic
sample by weight of carbon dioxide contained in sodium bicarbonate used.
(5) Divide the quotient into the apparent percent of carbon dioxide
in official sample to obtain percent of carbon dioxide evolved from the
[42 FR 14402, Mar. 15, 1977, as amended at 47 FR 11827, Mar. 19, 1982;
49 FR 10097, Mar. 19, 1984; 54 FR 24894, June 12, 1989; 58 FR 2877, Jan.
Additives that reference this regulation: